1. Field of the Invention
The present invention relates to millimeter band signal transmitting/receiving systems and houses provided with the same, and more specifically to a millimeter band signal transmitting/receiving system for indoor transmission of a video signal using a millimeter-wave and a house provided with the same.
2. Description of the Background Art
In millimeter-wave communication, if a path between a transmitter and receiver is obstructed by an object such as a human body, propagation of a direct wave traveling along a propagation path between the transmitter and receiver (hereinafter referred to as a line of sight) is interrupted as the millimeter-wave is absorbed by the object. It is a major concern in the millimeter-wave communication to ensure good communication even when the propagation path is obstructed by such object.
One attempt which has been made to ensure good reception with the line of sight obstructed is to provide the transmitter near the ceiling and to provide the receiver such that the propagation path is not obstructed by the object (that is, only direct wave is used). However, such approach is not actually practical in a general house particularly with many objects because of positional limitations of the transmitter and receiver.
Another approach relates to path diversity by a change in directivity of a terminal station antenna, macro diversity among a plurality of base stations or the like, as disclosed in “Fundamentals of Millimeter-wave Propagation” by Takeshi Manabe, in MWE '96 Microwave Workshop Digest, pp. 501–510. However, any of these approaches relates to a structure based on a fundamental that “one radiowave path is selectively used at a time and a plurality of radiowave paths are not simultaneously used” for transmission/reception of information apart from monitoring for the purpose of control. Thus, a system tends to be more complicated and requires a higher cost.
Therefore, the present invention is made to solve the aforementioned problem. An object of the present invention is to provide a millimeter band signal transmitting/receiving system for surely performing millimeter-wave communication with an extremely low cost and a simple method.